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Abstract:

A battery cell module includes a plurality of battery cells, in
particular lithium-ion battery cells which are arranged in a packet and
each of which has a substantially prismatic cell housing. Each cell
housing has the three dimensions: housing height, housing width, and
housing depth. Two of the dimensions are carried out in a substantially
identical manner in all the battery cells of the battery cell module, and
the third dimension is carried out differently in at least two battery
cells of the battery cell module. A battery includes said battery cell
module and a motor vehicle includes said battery.

Claims:

1. A battery cell module, comprising: a plurality of battery cells
arranged in a pack and each having a substantially prismatic cell
housing, wherein: a respective cell housing has the three dimensions:
housing height, housing width and housing depth, and two dimensions of
the three dimensions are substantially identical for all of the battery
cells of the plurality of battery cells, and a third dimension of the
three dimensions differs for at least two battery cells of the plurality
of battery cells.

2. The battery cell module as claimed in claim 1, wherein the two
dimensions are the housing height and the housing width and the third
dimension is the housing depth.

3. The battery cell module as claimed in claim 1, further comprising: a
pair of clamping plates of substantially equal size, wherein each
clamping plate of the pair of clamping plates is configured to bear
against a housing wall of an outer battery cell of the battery cell
module and to exert a force on said outer battery cell in a direction of
the other clamping plate of the pair of clamping plates.

4. The battery cell module as claimed in claim 1, further comprising: at
least one cooling plate configured to bear against an outer surface
formed by the pack of battery cells.

5. The battery cell module as claimed in claim 1, wherein: each battery
cell of the plurality of battery cells has a terminal, and terminals of
battery cells of a respective battery cell module are of substantially
identical configuration in terms of geometric dimensions.

6. A battery comprising: at least one battery cell module including: a
plurality of battery cells arranged in a pack and each having a
substantially prismatic cell housing, wherein: a respective cell housing
has the three dimensions: housing height, housing width and housing
depth, and two dimensions of the three dimensions are substantially
identical for all of the battery cells of the plurality of battery cells,
and a third dimension of the three dimensions differs for at least two
battery cells of the plurality of battery cells.

7. The battery as claimed in claim 6, wherein: the at least one battery
cell module is a plurality of battery cell modules including a first
battery cell module and a second battery cell module, the first battery
cell module includes at least one battery cell for which the third
dimension is larger or smaller than the third dimension of at least one
battery cell of the second battery cell module, and cooling plates
assigned to said first and second battery cell modules have substantially
identical dimensions and geometric shape.

8. The battery as claimed in claim 7, wherein said plurality of battery
cell modules are arranged stacked one above another.

9. A motor vehicle which can be driven by electric motor, comprising: at
least one battery having at least one battery cell module including: a
plurality of battery cells arranged in a pack and each having a
substantially prismatic cell housing, wherein: a respective cell housing
has the three dimensions: housing height, housing width and housing
depth, two dimensions of the three dimensions are substantially identical
for all of the battery cells of the plurality of battery cells, and a
third dimension of the three dimensions differs for at least two battery
cells of the plurality of battery cells, and the at least one battery is
connected to a drive system of the motor vehicle.

Description:

[0001] The present invention relates to a battery cell module which
comprises a multiplicity of battery cells which are arranged in a pack
and which have in each case a substantially prismatic cell housing,
wherein a respective cell housing has the three dimensions housing
height, housing width and housing depth.

[0002] The present invention also relates to a battery which comprises at
least one battery cell module according to the invention.

[0003] The present invention is supplemented by a motor vehicle which has
at least one battery according to the invention.

PRIOR ART

[0004] A battery which comprises one or more galvanic battery cells serves
as an electrochemical energy store and energy converter. During the
discharging of the battery or of the respective battery cell, chemical
energy stored in the battery is converted into electrical energy by way
of an electrochemical redox reaction. Said electrical energy can be
demanded by a user according to requirements.

[0005] In particular in hybrid and electric vehicles, in so-called battery
packs, use is made of lithium-ion batteries or nickel-metal hydride
batteries composed of a large number of electrochemical cells connected
in series. It is conventionally the case here that a battery management
system including a battery state detection means serves for safety
monitoring and for ensuring as long a service life as possible.

[0006] In the case of lithium-ion storage technology, a multiplicity of
individual battery cells are connected together to form an overall
battery. Here, each individual cell has a housing for encasing the active
battery cell components and the electrolyte. Only the electrical
terminals or poles of the battery cell project out of the battery cell
housing.

[0007] DE 690 22 892 T2 discloses a modular battery installation system
which is composed of a plurality of individual module units. Such
individual module units may be battery cells. These basic structural
units can, on the basis of the modular principle, form a battery assembly
of virtually any desired size.

[0008] DE 10 2007 052 375 A1 describes an energy store with more effective
cooling and a method for the inexpensive production of said energy store,
which method permits the production of an energy store to meet different
customer demands. It is also the case in the embodiment described in DE
10 2007 052 375 A1 that a compact and inexpensive modular design is
attained which can be used within the context of a modular system. It is
possible here, too, for virtually any desired number of cells to be
connected together to form modules.

[0009] Overall, therefore, it is known that battery cells designed for the
same applications or of similar type can be combined to form modules.
Here, however, no allowance is made for different types of battery cells
or battery cells for different applications. For example, the batteries
used in different types of electric vehicles are relatively different in
terms of their structural configurations and their external dimensions.
This results firstly from different power requirements and secondly from
different available installation space conditions or arrangement
positions. Furthermore, the different battery cells or batteries have
terminals which differ from one another, such as for example different
thread sizes. Said differences between the batteries or battery cells
makes the transport, storage and also handling and mounting thereof
relatively cumbersome. Furthermore, supply systems, positioning systems,
fixing systems, maintenance systems, temperature control systems and
handling systems must be of relatively complex design in order to allow
them to be used for the different battery cell types or battery types.

DISCLOSURE OF THE INVENTION

[0010] A battery cell module is provided which comprises a multiplicity of
battery cells, in particular lithium-ion battery cells, which are
arranged in a pack and which have in each case a substantially prismatic
cell housing, wherein a respective cell housing has the three dimensions
housing height, housing width and housing depth. According to the
invention, two of the dimensions are substantially identical for all of
the battery cells of the battery cell module, and the third dimension
differs for at least two battery cells of the battery cell module.

[0011] That is to say that the size of the third dimension may vary from
battery cell to battery cell, wherein the sizes of the first and second
dimensions are identical for every battery cell.

[0012] Here, the invention is not restricted to lithium-ion battery cells;
other battery cells, for example also nickel-metal hydride battery cells,
may alternatively be configured and arranged according to the invention.

[0013] Considering a prismatic battery cell to be placed on a base
surface, the housing height of said battery cell is the distance from the
base surface to a top surface which forms a termination of the battery
cell housing at the uppermost edge. The housing width corresponds to the
length of an edge of the base surface and runs perpendicular to the
housing height. The housing depth runs perpendicular to the housing
height and to the housing width and, in the case of a prismatic battery
cell with a rectangular base surface, runs correspondingly to the length
of a second edge of the base surface which runs perpendicular to the
first edge of the base surface.

[0014] In the case of step formations in the housing, for example in the
housing height, a corresponding housing has portions of different height.
According to the invention, identical height of the battery cells of the
module means in this case that all of the battery cells of the module
have the same step formation in terms of height, preferably also with
identical width of the step formation.

[0015] According to the invention, taking as a starting point normal
battery cells which are or can be placed, adjacent to one another, on
their base surfaces and which have in each case one prismatic cell
housing with a preferably rectangular base surface, said base surfaces
are of different size for at least two of the battery cells if, as the
third variable, the housing depth varies from battery cell to battery
cell. By contrast, front and rear side surfaces, which preferably stand
perpendicular to the base surface, are of equal size for each battery
cell. It is preferable for the three stated dimensions housing height,
housing width and housing depth to be the volume-defining dimensions of
the battery cell, that is to say the battery cell has no volume elements
other than the prismatic cell housing itself. The battery cells are
arranged in a pack, wherein in each case one or more intermediate layers
may if appropriate be provided between the battery cells. Said
intermediate layers are however formed so as to be relatively thin in
relation to the depths of the battery cells, such that the battery cells
arranged in the pack form a compact module.

ADVANTAGES OF THE INVENTION

[0016] The advantage of the invention lies in particular in the fact that,
owing to the standardization of at least two geometric dimensions of the
battery cells, it is made possible to standardize geometric parameters of
the surroundings of the battery cell module during its use, storage,
handling, transport and mounting. For example, if, for the same housing
height and housing width, only the depth of individual battery cells of
the battery cell module is varied, it is thus the case that two geometric
dimensions of the battery cell module as a whole, that is to say the
module width and the module height, are also fixedly predefined.
Variations of the battery cell module can exist only in its length owing
to different depths of individual battery cells. In one particular
refinement, it is possible, even despite different depths of individual
battery cells which are used, for the modules produced from said battery
cells to have equal lengths. As a result of the reliable adherence to
equal module widths and heights, it is possible for transport systems,
storage systems, supply systems, positioning systems, fixing systems,
maintenance systems, temperature control systems and handling systems to
be set up uniformly and, if appropriate, to be designed to be variable
only in terms of depth or length. In this way, it is possible for
transport systems, storage systems, supply systems and handling systems
to be of uniform and/or simpler design. The processes to be performed by
said systems are easier to compute. Temperature control or monitoring
systems can be designed with lower outlay in terms of parts. The
standardization of dimensions furthermore provides constraints for
further battery development, which have the effect of accelerating the
development process of battery cells and batteries.

[0017] It is preferable for the identical dimensions to be the housing
height and the housing width and for the dimension which distinguishes at
least two battery cells to be the housing depth. The housing depth is
thus definitive of the volume difference between the respective battery
cells. The greater the desired capacity of the cell, the greater the
battery cell depth should be.

[0018] The battery cell module according to the invention preferably
comprises a pair of clamping plates of substantially equal size, wherein
in each case one clamping plate bears against an outer housing wall of an
outer battery cell of the battery cell module and exerts a force on said
battery cell in the direction of the in each case other clamping plate.
The clamping force or clamping forces may be realized by means of
suitable clamping devices such as clamping bolts or belts, if appropriate
with the aid of spring elements. The advantage of said embodiment of the
invention lies in the fact that identical clamping plates can be used
despite the use of different battery cells.

[0019] In a further advantageous embodiment, it is provided that the
battery cell module according to the invention has at least one cooling
plate which bears against an outer surface formed by the pack of battery
cells. Said common outer surface is formed by the respective outer
surfaces of the individual battery cells, for example on the underside of
the pack of battery cells, such that a plurality, and preferably all, of
the undersides of the battery cells make contact with the cooling plate.
Owing to the identical dimension, for example the identical width of the
battery cells, it is preferably possible to use cooling plates which have
in each case a width matched to said standard width. Only the lengths of
the cooling plates may vary depending on the length of the respective
battery cell module. It is clear that, to produce such standardized
cooling plates, less production and assembly outlay is required and
simpler or fewer manufacturing means can be used.

[0020] Furthermore, terminals of the battery cells of a respective battery
cell module may be of substantially identical configuration in terms of
their geometric dimensions. Said terminals preferably comprise identical
shaped elements, such as for example connection means in the form of
threads. It may for example be provided that all of the terminals are
equipped with an M8 thread. Here, the expression "terminal" is to be
understood to mean the battery cell poles which project out of the
battery cell housing and which are connected in electrically conductive
fashion to the coils in the interior of the battery cell. The advantage
of this embodiment of the invention lies in the reduction of the number
of different types of cell connectors and in simplified mounting of said
cell connectors.

[0021] The invention also relates to a battery, in particular a
lithium-ion battery, which comprises at least one battery cell module
according to the invention. Depending on the demanded power, a battery
may have a multiplicity of such battery cell modules according to the
invention.

[0022] Here, a battery of said type may be designed such that a first
battery cell module comprises at least one battery cell for which the
third dimension is larger or smaller than the third dimension of at least
one battery cell of a second battery cell module, wherein the cooling
plates assigned to the battery cell modules have substantially the same
dimensions and the same geometric shape. In one design variant, all of
the battery cells of a module have the same third dimension, that is to
say the size of said dimension is the same for all of the battery cells
of the module. Here, different numbers of battery cells may be connected
to one another to form modules such that the entirety of the battery
cells of one module can be arranged on a cooling plate with substantially
the same dimensions as the cooling plate assigned to another module. The
advantage of this configuration lies in the fact that, despite the
different third dimension, for example despite different depths of the
individual battery cells in the individual modules and different numbers
of battery cells, identical cooling plates can be used.

[0023] In one particular embodiment of the battery according to the
invention, it is provided that the battery cell modules are arranged
stacked one above the other. Owing to identical base surface dimensions,
said battery cell modules are particularly well suited to being stacked,
in particular if the battery cells have been combined to form modules in
such a way that the modules have identical lengths despite different
depths of the individual battery cells. In the case of possibly different
lengths of the modules, it is possible to realize offset stacking, which
however leads to improved strength of the battery cell stack. That is to
say that, according to the invention, the battery cells can likewise be
arranged in a modular system and one above the other to form a battery.

[0024] The invention also comprises a motor vehicle and in particular a
motor vehicle which can be driven by electric motor, which motor vehicle
has at least one battery with the battery cell module according to the
invention, wherein the battery is connected to a drive system of the
motor vehicle.

DRAWINGS

[0025] Exemplary embodiments of the invention will be explained in more
detail on the basis of the drawings and the following description. In the
drawings:

[0029] FIG. 1 shows the general construction of a battery cell module
according to the invention. Said battery cell module is assembled from
individual battery cells 1. Each battery cell 1 has a volume-defining
cell housing 10. It can be clearly seen that the battery cells 1 have in
each case an identical housing height 11 and housing width 12.

[0030] Each of the illustrated battery cells has a different housing depth
13. Each of the illustrated battery cells 1 thus has a different volume.
Despite the use of battery cells 1 with different volumes and accordingly
with different capacities, it is possible for the battery cells 1 to be
arranged as illustrated in FIG. 1 such that they can for example be
transported, stored or mounted together in a simple manner. On the top
sides, the battery cells 1 each have terminals 40. Said terminals are
preferably likewise of identical design with regard to their geometric
dimensions and/or connection means, such that identical connectors can be
used for connecting the battery cells to one another and for connecting
to other batteries.

[0031] The individual battery cells 1 which are combined to form packs
may, as modules, be placed on and/or covered by cooling plates 30. As
illustrated in FIG. 2, it is for example possible for a first battery
cell module 50 and a second battery cell module 60 to be arranged on a
cooling plate 30. According to FIG. 3, however, it is also possible for
only one battery cell module to be arranged on a cooling plate 30 having
the same geometric dimensions as the cooling plate according to FIG. 2.
Owing to the smaller housing depth 13 of the battery cells 1 used in FIG.
2, twice as many battery cells can be arranged on the cooling plate 30 as
can be arranged on the cooling plate 30 in FIG. 3.

[0032] The invention is however not restricted to the arrangement of two
battery cell modules 50, 60 on a longer cooling plate 30; it would rather
also be possible to arrange on said cooling plate 30 only one battery
cell module as in FIG. 3, but with twice the number of battery cells 1.

[0033] The respective module length 70 is thus determined by the different
depths 13 of the individual battery cells 1 and the number of battery
cells 1 arranged in each module.

[0034] The battery cells illustrated in FIGS. 2 and 3 may, as illustrated
in FIG. 1, have different housing depths 13, whereby further variations
in module lengths 70 can be realized.

[0035] It is advantageous for a certain number of battery cells 1 in a
battery cell module to be held together by means of a first clamping
plate 20 and a second clamping plate 21. A respective clamping plate 20,
21 bears against the housing wall of in each case one outer battery cell
14 and is pulled or pushed in each case in the direction of the other
clamping plate by suitable clamping means. Owing to the use of battery
cells 1 with identical housing height 11 and identical housing width 12,
it is likewise possible to use clamping plates of equal size, such that
less outlay is required with regard to the production and mounting of the
clamping plates.